Agreements - Additional Information (Detail)							1 Months Ended		3 Months Ended				36 Months Ended
	Jul. 11, 2025 USD ($)	Jul. 11, 2024 USD ($)	Jul. 11, 2023 USD ($)	Jan. 24, 2023	Jul. 11, 2022 USD ($)	Oct. 26, 2012	Jul. 31, 2023 USD ($) shares	Jul. 31, 2023 SFr / shares	Mar. 31, 2025 USD ($)	Mar. 31, 2025 USD ($) SFr / shares	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Jul. 11, 2025 USD ($)	Sep. 30, 2024	Oct. 26, 2023 USD ($)	Jul. 19, 2023
License Agreement [Line Items]
Research and development expenses									$ 3,887,000		$ 2,581,000
Asset acquisition equity interests issued or issuable number of shares issued | shares							1,414,688
Asset Acquisition Percentage Of Outstanding Ordinary Shares							11.26%
U.S. Rights for FYCOMPA [Member]
License Agreement [Line Items]
Date on which strategic collaboration is entered into				Jan. 24, 2023
Payments to acquire productive assets									164,200,000
Contingent consideration liability									$ 25,000,000	$ 25,000,000
U.S. Rights for FYCOMPA [Member] | Royalty More Than Ten Million And Less Than Hundred Million [Member]
License Agreement [Line Items]
Percentage of royalty on net sales									6.00%
U.S. Rights for FYCOMPA [Member] | Royalty More Than Ten Million And Less Than Hundred Million [Member] | Royalty Agreement Terms [Member]
License Agreement [Line Items]
Percentage of royalty on net sales									12.00%
U.S. Rights for FYCOMPA [Member] | Royalty More Than Hundred And Twenty Five Million [Member]
License Agreement [Line Items]
Percentage of royalty on net sales									11.00%
Net sales royalty threshold									$ 125,000,000
U.S. Rights for FYCOMPA [Member] | Royalty More Than Hundred And Twenty Five Million [Member] | Royalty Agreement Terms [Member]
License Agreement [Line Items]
Percentage of royalty on net sales									22.00%
U.S. Rights for FYCOMPA [Member] | Royalty More Than Hundred Million And Less Than Hundred And Twenty Five Million [Member]
License Agreement [Line Items]
Percentage of royalty on net sales									8.50%
U.S. Rights for FYCOMPA [Member] | Royalty More Than Hundred Million And Less Than Hundred And Twenty Five Million [Member] | Royalty Agreement Terms [Member]
License Agreement [Line Items]
Percentage of royalty on net sales									17.00%
AGAMREE [Member]
License Agreement [Line Items]
Payments to acquire productive assets							$ 75,000,000
Asset acquisition equity interests issued or issuable number of shares issued | shares							1,414,688
Asset Acquisition Percentage Of Outstanding Ordinary Shares							11.26%
Asset Acquisition Investment Share Price | SFr / shares										$ 9.477
Closing Market Price | SFr / shares								SFr 8.25
Foreign Currency Exchange Rate, Translation																1.1537
Collaborative arrangement, milestone payment obligation															$ 36,000,000
Payment on milestone payment												$ 36,000,000
Capitalized amortized Cost												$ 36,000,000
Finite-lived intangible asset, useful life														10 years 6 months
AGAMREE [Member] | Royalty Less Than Hundred Million [Member]
License Agreement [Line Items]
Percentage of royalty on net sales									5.00%
AGAMREE [Member] | Royalty More Than Hundred Million And Less Than Two Hundred Million [Member]
License Agreement [Line Items]
Percentage of royalty on net sales									7.00%
AGAMREE [Member] | Royalty More Than Two Hundred Million And Less Than Three Hundred Million [Member]
License Agreement [Line Items]
Percentage of royalty on net sales									9.00%
AGAMREE [Member] | Royalty More Than Three Hundred Million [Member]
License Agreement [Line Items]
Percentage of royalty on net sales									11.00%
AGAMREE [Member] | Royalty Less Than Two Hundred Fifty Million [Member]
License Agreement [Line Items]
Percentage of royalty on net sales									7.00%
AGAMREE [Member] | Royalty More Two Hundred And Fifty Million And Less Than Five Hundred Million [Member]
License Agreement [Line Items]
Percentage of royalty on net sales									8.50%
AGAMREE [Member] | Royalty More Than Five Hundred Million And Less Than Seven Hundred Fifty Million [Member]
License Agreement [Line Items]
Percentage of royalty on net sales									10.00%
AGAMREE [Member] | Royalty More Seven Hundred And Fifty Million And Less Than One Billion [Member]
License Agreement [Line Items]
Percentage of royalty on net sales									12.00%
AGAMREE [Member] | Royalty More Than One Billion And Less Than Two Billion [Member]
License Agreement [Line Items]
Percentage of royalty on net sales									13.00%
AGAMREE [Member] | Royalty More Than Two Billion [Member]
License Agreement [Line Items]
Percentage of royalty on net sales									15.00%
AGAMREE [Member] | Royalty For Santhera Sales Based Milestones [Member]
License Agreement [Line Items]
Net sales based milestone to royalty threshold									$ 105,000,000
Net sales based milestone upon achievement of revenues									12,500,000
Revenue milestones									$ 100,000,000
AGAMREE [Member] | Royalty For Additional Indications And Milestones Of Up To Fifty Million More [Member]
License Agreement [Line Items]
Percentage of royalty payable to sales based milestone									11.00%
AGAMREE [Member] | Royalty For Additional Indications And Milestones [Member]
License Agreement [Line Items]
Contingent consideration liability									$ 50,000,000	$ 50,000,000
Minimum [Member] | U.S. Rights for FYCOMPA [Member] | Royalty More Than Ten Million And Less Than Hundred Million [Member]
License Agreement [Line Items]
Net sales royalty threshold									10,000,000
Minimum [Member] | U.S. Rights for FYCOMPA [Member] | Royalty More Than Ten Million And Less Than Hundred Million [Member] | Royalty Agreement Terms [Member]
License Agreement [Line Items]
Net sales royalty threshold									10,000,000
Minimum [Member] | U.S. Rights for FYCOMPA [Member] | Royalty More Than Hundred And Twenty Five Million [Member] | Royalty Agreement Terms [Member]
License Agreement [Line Items]
Net sales royalty threshold									125,000,000
Minimum [Member] | U.S. Rights for FYCOMPA [Member] | Royalty More Than Hundred Million And Less Than Hundred And Twenty Five Million [Member]
License Agreement [Line Items]
Net sales royalty threshold									100,000,000
Minimum [Member] | U.S. Rights for FYCOMPA [Member] | Royalty More Than Hundred Million And Less Than Hundred And Twenty Five Million [Member] | Royalty Agreement Terms [Member]
License Agreement [Line Items]
Net sales royalty threshold									100,000,000
Minimum [Member] | AGAMREE [Member] | Royalty More Than Hundred Million And Less Than Two Hundred Million [Member]
License Agreement [Line Items]
Net sales royalty threshold									100,000,000
Minimum [Member] | AGAMREE [Member] | Royalty More Than Two Hundred Million And Less Than Three Hundred Million [Member]
License Agreement [Line Items]
Net sales royalty threshold									200,000,000
Minimum [Member] | AGAMREE [Member] | Royalty More Than Three Hundred Million [Member]
License Agreement [Line Items]
Net sales royalty threshold									300,000,000
Minimum [Member] | AGAMREE [Member] | Royalty More Two Hundred And Fifty Million And Less Than Five Hundred Million [Member]
License Agreement [Line Items]
Net sales royalty threshold									250,000,000
Minimum [Member] | AGAMREE [Member] | Royalty More Than Five Hundred Million And Less Than Seven Hundred Fifty Million [Member]
License Agreement [Line Items]
Net sales royalty threshold									500,000,000
Minimum [Member] | AGAMREE [Member] | Royalty More Seven Hundred And Fifty Million And Less Than One Billion [Member]
License Agreement [Line Items]
Net sales royalty threshold									750,000,000
Minimum [Member] | AGAMREE [Member] | Royalty More Than One Billion And Less Than Two Billion [Member]
License Agreement [Line Items]
Net sales royalty threshold									1,000,000,000
Minimum [Member] | AGAMREE [Member] | Royalty More Than Two Billion [Member]
License Agreement [Line Items]
Net sales royalty threshold									2,000,000,000
Maximum [Member] | U.S. Rights for FYCOMPA [Member] | Royalty More Than Ten Million And Less Than Hundred Million [Member]
License Agreement [Line Items]
Net sales royalty threshold									100,000,000
Maximum [Member] | U.S. Rights for FYCOMPA [Member] | Royalty More Than Ten Million And Less Than Hundred Million [Member] | Royalty Agreement Terms [Member]
License Agreement [Line Items]
Net sales royalty threshold									100,000,000
Maximum [Member] | U.S. Rights for FYCOMPA [Member] | Royalty More Than Hundred Million And Less Than Hundred And Twenty Five Million [Member]
License Agreement [Line Items]
Net sales royalty threshold									125,000
Maximum [Member] | U.S. Rights for FYCOMPA [Member] | Royalty More Than Hundred Million And Less Than Hundred And Twenty Five Million [Member] | Royalty Agreement Terms [Member]
License Agreement [Line Items]
Net sales royalty threshold									125,000,000
Maximum [Member] | AGAMREE [Member] | Royalty Less Than Hundred Million [Member]
License Agreement [Line Items]
Net sales royalty threshold									100,000,000
Maximum [Member] | AGAMREE [Member] | Royalty More Than Hundred Million And Less Than Two Hundred Million [Member]
License Agreement [Line Items]
Net sales royalty threshold									200,000,000
Maximum [Member] | AGAMREE [Member] | Royalty More Than Two Hundred Million And Less Than Three Hundred Million [Member]
License Agreement [Line Items]
Net sales royalty threshold									300,000,000
Maximum [Member] | AGAMREE [Member] | Royalty Less Than Two Hundred Fifty Million [Member]
License Agreement [Line Items]
Net sales royalty threshold									250,000,000
Maximum [Member] | AGAMREE [Member] | Royalty More Two Hundred And Fifty Million And Less Than Five Hundred Million [Member]
License Agreement [Line Items]
Net sales royalty threshold									500,000,000
Maximum [Member] | AGAMREE [Member] | Royalty More Than Five Hundred Million And Less Than Seven Hundred Fifty Million [Member]
License Agreement [Line Items]
Net sales royalty threshold									750,000,000
Maximum [Member] | AGAMREE [Member] | Royalty More Seven Hundred And Fifty Million And Less Than One Billion [Member]
License Agreement [Line Items]
Net sales royalty threshold									1,000,000,000
Maximum [Member] | AGAMREE [Member] | Royalty More Than One Billion And Less Than Two Billion [Member]
License Agreement [Line Items]
Net sales royalty threshold									$ 2,000,000,000
License Agreement with BioMarin [Member]
License Agreement [Line Items]
Date on which strategic collaboration is entered into						Oct. 26, 2012
Percentage of royalty on net sales									3.50%
Net sales royalty threshold									$ 100,000,000
License Agreement with BioMarin [Member] | Minimum [Member]
License Agreement [Line Items]
Royalty agreement period									7 years
Percentage of royalty on net sales									7.00%
License Agreement with BioMarin [Member] | Maximum [Member]
License Agreement [Line Items]
Percentage of royalty on net sales									10.00%
License Agreement For RUZURGI [Member]
License Agreement [Line Items]
Date on which strategic collaboration is entered into					Jul. 11, 2022
Minimum royalty	$ 3,000,000	$ 3,000,000	$ 3,000,000		$ 3,000,000								$ 3,000,000
Up front payment					$ 10,000,000
Asset acquisition purchase price consideration		$ 10,000,000	$ 10,000,000
Amount of minimum royalty payable maturity terms not met									$ 5,000,000
License Agreement For RUZURGI [Member] | Minimum [Member]
License Agreement [Line Items]
Percentage of minimum royalty payable to net sales									1.25%
License Agreement For RUZURGI [Member] | Maximum [Member]
License Agreement [Line Items]
Percentage of minimum royalty payable to net sales									2.50%